Almost all of the demons in this node are weak to Light. The goal is to go first, and get your demons to spam Hama to get extra press turns and easily kill the demons. They all need the Ward set because without it, they will get statused when it's the enemy's turn to act. There's a timer of 3 turns per wave that you need to hit, and the timer for the last wave is a lot shorter due to Lucifer being a threat with Morning Star and Megidolaon spam.

Demons:

Sleipnir is used because of innate Light Boost + Speedster as well as access to Mahamaon.

Purple Mastema is an extremely powerful Light element attacker. It's overkill, but if you do happen to have access to a Mastema of any archetype, use it.

Brands should be Divine + Ward, prioritize MATK then Speed. You can take Hama instead of Hamaon on Mermaid if you run Spell Brands.

Judgement Light can work as better replacement of Hama when the Dx2 is Eileen due her skills Fragant Lily, Lucky Press II, Post Script and Happy Ending. Getting Judgement Light and level it tends to be uncommon and difficult.